You can't do that because the SS signal is an input on your slave Arduino, it needs to be held low for the SPI hardware to work. The quickest way to do this (just to get things working) is to plug a wire (aka flying wire/lead) in with one end in a GND hole (one the Arduino headers) and the other end into the SS input, D10 on the Duemilanove and D53 on Mega. (not sure what you have).

I hope that's correct, but I don't understand how the slave detects the speed and mode ETC and I notice we don't seem to have included any SPI library. Could you please explain? Is the code SPCR |= _BV(SPE); some sort of built ASM cmd I don't see a reference to it in the SPI reference page?Should there not be some SPI library included and some settings made ie setClockDivider()

failing my setup it has to be that a flight detection is required, in which case I need Synco and will have to wait until he gets back to NZ to chek on that

You can't do that because the SS signal is an input on your slave Arduino, it needs to be held low for the SPI hardware to work.

From the Atmega manual, p171:

Quote

When the SPI is configured as a Slave, the Slave Select (SS) pin is always input. When SS is held low, the SPI is activated, and MISO becomes an output if configured so by the user. All other pins are inputs. When SS is driven high, all pins are inputs, and the SPI is passive, whichmeans that it will not receive incoming data. Note that the SPI logic will be reset once the SS pin is driven high.

So if your Arduino is an SPI slave, then pin 10 (for the Uno and variants) needs to be low or nothing will happen. As Graynomad said, grounding it should work.

My slave example didn't need the SPI library because the SPI library was designed for the master end. There is nothing particularly useful for slaves. Can you post your code? You should have the stuff in setup like this:

It's possible it's inactive I suppose. Without reading the datasheet it is hard to be sure. Your "fake" launch may prove things. The other thing would be, if possible, to hook up a scope or logic analyzer and try to see if the SCK is being pulsed at all. You would need to check you have the device configured correctly.

Please post technical questions on the forum, not by personal message. Thanks!

Hi Gents, Can I just check something with you, testing tonight I noticed that when the SPI connection is plugged into the Arduino the LED marked L is flashing very faintly. Looking at the schematic this looks to be the SCK working would you agree? if so is this normal? doe sthe SCK continually send a pulse? or does thsi idicate the SPI is pumping data out were just not seeing it?